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"Ballooning" Spiders Use Electrostatic Forces To Generate Lift
KentuckyFC writes "Many types of small spider release threads into the air which then lift and carry them significant distances. Biologists have found them at altitudes of up to 4 km. The conventional thinking is that the threads catch thermal air currents which then carry them away but this does not explain how spiders perform their trick even when there is little or no wind. Now one physicist says the explanation is the atmosphere's natural electric field which has an average downward-pointing magnitude of 120 Volts per metre. He calculates that a strand of silk need only gain a negative charge of around 30 nanoCoulombs to lift a spider. That explains how the spiders take off on windless days, how they reach such great heights and how several strands can lift heavier spiders of up to 100 milligrams."
The bat signal itself doesn't fit with physics.
My parents have owned a searchlight rental business for 30 years now. For the first Batman movie they were asked to put a bat signal cutout on the searchlight to simulate the bat signal. The thing is that searchlights have too high a candlepower and the light just bends around the cutout. The light spreads more the farther away from the searchlight. It looks cool when shown against a wall, but far out in the sky it simply doesn't work. The physics of light doesn't allow it.